You can use the image at the top of your page to navigate between accounts. This allows you and your family or friends to more quickly switch between Facebook accounts while using the same computer.

You can choose whether or not to save your password for quicker login. If you select Remember my password, you'll remain logged in to Facebook without having to re-enter your password each time you log in. You can also remove saved login information from your account and add extra security.

The rationale for the multiple logins isn't yet clear and Facebook declined to provide one. But the feature does raise some interesting questions. Does Facebook view it as a possible engine of growth — a way to encourage users to establish multiple accounts? How will the company prevent people from using the feature to create fake accounts — a common practice on Instagram called the "finsta." And wouldn't such accounts violate Facebook's Real Names policy and open Facebook up to further exploitation by trolls?

Facebook has not yet responded to those questions. We'll update if it does.